Motor Swap SectionTech and Follow-My-Build Threads for members looking to put a different engine in their Mustang

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Id like to add a little side note, im not sure if you checked this out or not. When i first did my 97 cobra 4v swap in my gt, I re-used the GT computer and it ran fine and i had no problems at all. When I put the car on the dyno a month or two later the car only made 190rwhp. The guys at SGS pointed to my attention that the 97 GT computer did not have the parameters in it for the IMRC plates and in turn they did not open. The only fix was to either delete the IMRC or use a cobra ECU. I opted for the deletes.

The GT tune wont allow it. The A/F ratio just 0's out at 6K RPM and you loose all power. Scared the crap out of me when I discovered it.

Quote:

Originally Posted by 1nstysnake

Ill take one Motivation gi gigii gigidi doo quote from quagmire[ familyguy]
to the op nicely done how long did your project take after everything done for the swap?

From the day I pulled it to the day it was road worthy, 19 days. That included pulling the old engine on Tuesday, waiting till till that weekend to go to the pick U pull, then finding the exhaust manifolds and waiting on them to ship my throttle cable, then assembly and install. I would say 3 days of actual work if you had all of the parts that you needed. A day to pull it, a half day to assemble, and a full day and a half to install.

Quote:

Originally Posted by uberstang1

Id like to add a little side note, im not sure if you checked this out or not. When i first did my 97 cobra 4v swap in my gt, I re-used the GT computer and it ran fine and i had no problems at all. When I put the car on the dyno a month or two later the car only made 190rwhp. The guys at SGS pointed to my attention that the 97 GT computer did not have the parameters in it for the IMRC plates and in turn they did not open. The only fix was to either delete the IMRC or use a cobra ECU. I opted for the deletes.

I didn't use the IMRC's. I loose some low end grunt, but it's not that bad really. It starts screaming at 3K RPM. I addressed if you wanted to keep the IMRC plates, you would have to use an RPM window switch and a set of relays to activate and deactivate the motor. Much like a Nitrous setup.

The GT tune wont allow it. The A/F ratio just 0's out at 6K RPM and you loose all power. Scared the crap out of me when I discovered it.

From the day I pulled it to the day it was road worthy, 19 days. That included pulling the old engine on Tuesday, waiting till till that weekend to go to the pick U pull, then finding the exhaust manifolds and waiting on them to ship my throttle cable, then assembly and install. I would say 3 days of actual work if you had all of the parts that you needed. A day to pull it, a half day to assemble, and a full day and a half to install.

I didn't use the IMRC's. I loose some low end grunt, but it's not that bad really. It starts screaming at 3K RPM. I addressed if you wanted to keep the IMRC plates, you would have to use an RPM window switch and a set of relays to activate and deactivate the motor. Much like a Nitrous setup.

so that should be in the "what you will need" section right- the ecu? I just doesn't make sense that a motor that can revv up to about 7k only b revved at 5800 or so. Do you plan on changin the ecu? To be honest, I don't really know what I'm talkin about but help me out.

I swapped out my NPI gt to a PI04gt motor and still have the NPI gt tune. Now, I have the 04gt ecu but idk if I can simply switch it out. Which is why I ask if you can do the same, put a cobra ecu on your car.

so that should be in the "what you will need" section right- the ecu? I just doesn't make sense that a motor that can revv up to about 7k only b revved at 5800 or so. Do you plan on changin the ecu? To be honest, I don't really know what I'm talkin about but help me out.

I swapped out my NPI gt to a PI04gt motor and still have the NPI gt tune. Now, I have the 04gt ecu but idk if I can simply switch it out. Which is why I ask if you can do the same, put a cobra ecu on your car.

The Mark VIII redlines at 6K RPM just like the Mustang GT does. That is why I never bothered. You can just get a tuner to change everything out if you want. If you swap the PCM, then the anti theft system will get all pissy.

The Mark VIII redlines at 6K RPM just like the Mustang GT does. That is why I never bothered. You can just get a tuner to change everything out if you want. If you swap the PCM, then the anti theft system will get all pissy.

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